If I wanted to spend $30,000 on a heated dog house with running water, I'd build a big kennel building and at least add to the value of my property. That's insane. But, like jtm said, if people have enough money, they don't care how much things cost. I wish I could just have the $30,000---I could live for at least a year on it.
I've seen some catalogs that sell stuff for kids that have prices like $15,000 for a princess canopy bed (give me $50, a trip to the craft store, and a screw gun and I can make one!), $5,000 for a fancy dresser, $3,000 for a big stuffed giraffe, etc. It's like some people can't find normal stuff to spend their money on so they have to look for overpriced junk to buy. They should just donate the extra money....they'd at least get a tax break.